I agree with most of what Laurence says apart from the fact that I never normaly use my compass when out on my bike.   I guess I do have a good sence of direction though.  The only time I would realy contemplate using it would be if I managed to realy get lost but when your following paths thats actualy fairly hard and my first point for recovery is the countours because they tend to be right whereas the paths may be wrong on the map. 

Doing it solo I put the descriptions in a plastic bag tied with string around my neck and then put it down the front of my shirt most of the time but it means I can readily get at the descriptions without having to stop.

 Ifor